I have the fax function on mine, but not to sound like a dunce, I've never used it. I just scan and email. It is so seldom I need to fax something, like once a year, it's not worth it learning how.
Also, the last time I had to fax some legal stuff, it was many pages long, and I don't have the capability to merge PDF files. Nothing I had ever needed, and still don't
Since I didn't want to send over 20 separate files, I walked the papers down to the Office Depot where they faxed it.
Some gig billing job I had a while back required I keep copies of paperwork, and again, I would go to Office Depot, have then scan all the papers into one file, and email it back to me or put on a jump drive. The cost was charged to the company I did billing for. Just a couple/three bucks or something.
May not have been the ultimate efficient way to do it, but it worked easily enough.